Cruising the galaxy in his space ship "The Orbit Jet" Space Ranger, Rocky Jones (Richard Crane), Vena Ray (Sally Mansfield), and 10 year-old Bobby (Robert Lyden) defend the Earth and themselves against space-bound evil doers.
A couple of missiles strike earth and Rocky and the gang go to find out where they are coming from. They end up on a moon of Jupiter which is perfect for their survival. They are lucky to land because they have run out of gas. At least their gas gauge says so.